Tips before starting
- With GC, I’m still figuring out what I must decide before I choose to add or amend something and what I can edit after I’ve made a change.
- You cannot edit the data table directly.
- You CAN replace data – click “reupload” – but the columns must match between original and replacement data.
- Click Save often when making the map. You never know when Adobe Flash is going to quit on you.
One of the busiest locations in Chicago, for people walking, or riding buses and trains. Also a lot of taxi traffic and medium bike traffic. At Adams Street and Riverside Plaza (er, the Chicago River).
- Prepare your data.”We support Spreadsheets (as CSVs), Shapefiles, KML, RSS, ATOM and GeoRSS.Â We also support WMS and Tile services!” GeoCommons has instructions on how to prepare your spreadsheets for geocoding (if not already geocoded; GC will also work with predefined XY coordinates or street addresses). Ensure fields holding numbers have their type set as numeric in the GIS or spreadsheet program or you may run into roadblocks later on when trying to analyze these fields.
- If uploading a shapefile, GC requires the SHX and DBF files as well. The PRJ file will also help GC know how to reproject your data on the fly. GC base layer maps are projected in WGS84, just like Google Maps. Without the PRJ file, your data may not show. [Can the user set projection?]
- Upload data.
- You need to turn your newly uploaded data from a “pending dataset” to a completed dataset. In this process you will tell GC a little more about your data, including which columns hold the XY coordinates (even though it guesses this). you can also change the attribute names and describe the content of those attributes (you can also change this later).
- So click “Next Step” to start this process.
- In the “Review Your Geodata” step, you may see that GC has found some additional columns in your dataset. I’m not sure why this is. Delete these columns by selecting the header and clicking Delete Column. Then click Save Changes. You can select multiple columns at a time by holding the Command (Mac) or Control (Windows) keys.
- Add metadata; edit attribute names and add descriptions.
- You’re done. GC will present you a page with statistics and options to download your data in different formats.
- If you want to make a map with more data, follow the process again starting at Step 1. If not, continue.
- Make a map! Click “Map Data” or the “Make a Map” button in toolbar.
- A map of the world will load. When GC has finished loading your “new layer,” the map will zoom in.
- For the pedestrian map, I want to symbolize the data with a single color but changing the size of the circle based how many people were counted there (your data must have this attribute in numeric form – if it doesn’t you may have to reupload your data). Click “Add Data” and then in the Map Brewer box that appears by:
- Click on Visual Theme. Click next.
- Select the NUMERIC attribute. In the pedestrian data, this is “count.”
- Then select whether or not you want colors or sizes. You can not change this later. You would just delete the layer and add the layer again (using your already uploaded dataset).
- Select what type of classification you want. This is entirely up to you and how you want the map to look and based on what data you have. You can change this later.
- Choose your shape and color.
- Add more data by clicking Add Data button. I think my map would be more useful and interesting if it also showed where the train stations are, a major destination category for people who walk downtown on weekdays. I will symbolize by a solid color. Instead of visual theme, which I chose for the ped counts, I will just choose Points, Lines & Areas. At this time, GC doesn’t allow custom icons.
- Re-order layers by dragging them up and down in the layers box. Click on the boxy “handle” to the left of the layer.
- Change the layer names by single clicking on the layer name. Press Enter when you’re done.
- Change the map name by singe click on it. Press Enter when you’re done.
After creating my pedestrian map, I had some suggestions for GeoCommons, the people who collected the pedestrian count data, and my own map.
- GeoCommons should add a map preview image for better sharing on Facebook and other websites that look for this.
- GeoCommons should allow maps to be private after creation – I think after you click save, they are added to a gallery (I could be wrong).
- The data collectors should add more locations, particularly around Union Station and the two Clinton CTA stations (also between CTA and Metra stations).
- The data collectors should add “date collected” to the data table
- The data collectors should extend survey hours to better match commuting patterns. A majority of the collections end at 5:45 PM while Metra’s rush hour ends just before 7 PM (this is when train departure frequency drops).
- I should add ridership data to the train stations so we can see which CTA and Metra stations are most used.